Mediated approaches for influencing physical activity: Update of the evidence on mass media, print, telephone and website delivery of interventions

The aim of this paper is to review evidence published since 1997 on the effectiveness of mass media, print, telephone and website-delivered physical activity (PA) interventions. For mass media, there is consistent evidence for impacts on recall of campaign tag lines and message content and modest evidence of short-term impacts on behaviour in some population subgroups. Print-based delivery of programs can have a modest impact on behaviour; research is needed on supplementary strategies to support print programs. Although there is a strong case for the potential of telephone and Internet delivered interventions, there is as yet little evidence that they can be effective. All of these 'mediated' approaches to PA program delivery are likely to be important elements of future public health interventions. The body of evidence for their effectiveness in changing behaviour is currently modest, however, and it is clear that these approaches have not yet been fully developed and evaluated. Combinations of different media and mutually supportive, integrated strategies are likely to be more effective and need to be developed and evaluated systematically, building on the current research evidence base.

Test-retest reliability of four physical activity measures used in population surveys

Accurate monitoring of prevalence and trends in population levels of physical activity (PA) is a fundamental public health need. Test-retest reliability (repeatability) was assessed in population samples for four self-report PA measures: the Active Australia survey (AA, N=356), the short International Physical Activity Questionnaire (IPAQ, N=104), the physical activity items in the Behavioral Risk Factor Surveillance System (BRFSS, N=127) and in the Australian National Health Survey (NHS, N=122). Percent agreement and Kappa statistics were used to assess reliability of classification of activity status as 'active', 'insufficiently active' or 'sedentary'. Intraclass correlations (ICCs) were used to assess agreement on minutes of activity reported for each item of each survey and for total minutes. Percent agreement scores for activity status were very good on all four instruments, ranging from 60% for the NHS to 79% for the IPAQ. Corresponding Kappa statistics ranged from 0.40 (NHS) to 0.52 (AA). For individual items, ICCs were highest for walking (0.45 to 0.78) and vigorous activity (0.22 to 0.64) and lowest for the moderate questions (0.16 to 0.44). All four measures provide acceptable levels of test-retest reliability for assessing both activity status and sedentariness, and moderate reliability for assessing total minutes of activity.

Muscle metabolism during sprint exercise in man: Influence of sprint training

In order to examine the influence of sprint training on metabolism and exercise performance during sprint exercise, 16 recreationally-active, untrained, men (TO2peak= 3.8+/-0.1 1.min(-1)) were randomly assigned to either a training (n=8) or control group (n=8). Each subject performed a 30-sec cycle sprint and a test to measure VO2peak before and after eight weeks of sprint training. The training group completed a series of sprints three times per week which progressed from three 30-sec cycle sprints in weeks 1 and 2, to six 30-sec sprints in weeks 7 and 8. Three mins of passive recovery separated each sprint throughout the training period. Muscle samples were obtained at rest and immediately following the pre- and post-training sprints and analysed for high energy phosphagens, glycogen and lactate; the activities of both phosphofructokinase (PFK) and citrate synthase (CS) were also measured and muscle fibre types were quantified, Training resulted in a 7.1% increase in mean power output (p

Developments in National Physical Activity Policy: An international review and recommendations towards better practice

Physical activity (PA) is increasingly considered an important public health issue and as such requires the development of good public health policy. This paper provides a summary of the literature on policy development and defines what a policy on PA may usefully comprise. The results of an international review of national level PA policies, using a defined set of criteria, are reported. Considerable similarities were found in the methods and approaches to policy development on PA across countries, with most adopting an intersectoral approach, with consultation and partnership between sectors occurring at a high level of government. The need for action across the lifespan is recognised, as is the need for multiple strategies across a variety of settings. A review of Australian PA policy found that, after promising strategic developments through Active Australia in the late 1990s, PA policy and the role of the federal health sector has become less clear, with PA policy existing now only as a component part integrated into other chronic disease prevention policy initiatives. Recommendations towards better practice in policy making are made with particular reference to developing a clearly defined integrated national PA policy in the Australian context.